Custom categories element for QuickForm

Hello everyone, I just started to use QuickForm recently and I like it, however, I want to create a way to select categories in a certain way and I am not sure how to approach it. I'm working on a CMS, and for it I have multiple categories and sub categories that the user can select for each article. Now, I need to somehow, create a list of categories and sub categories in QuickForm. I was thinking of using a check box for each and its name next to it, and then the user can check each check box that corresponds to the category they want the article in. I am not sure how to approach this using QuickForm. Perhaps somebody has already made something like this someplace else and can point me in the right direction. I was thinking I would need to create a custom element somehow, but I'm not sure if I should create one off of the group element or the check box element. Thanks. Ben